Clients (windows) are organized in a tree data structure within containers. The tree branches via horizontal or vertical splits, and containers can also be set to tabbed or stacked layouts. Floating windows are available for corner cases that don't mix well with tiling, and remain on a separate layer above the tiled windows.

Application launcher

By default i3-dmenu-desktop is used as a wrapper for dmenu. i3-dmenu-desktop creates a list of all installed applications via their .desktop files. There is a rewrite of this perl script called [github.com/enkore/j4-dmenu-desktop j4-dmenu-desktop], which is a near-drop-in replacement for the script shipped with i3, but much faster.

Clipboard (copy & paste issues)

By default, when you close a window, the buffer with the clipboard info will disappear. You have to use a clipboard manager like clipit to avoid that.